Numerical design and analysis of a langevin power ultrasonic transducer for acoustic cavitation generation

• Published in: Sensors and actuators. A. Physical. 2020-08, Vol.311, p.112035, Article 112035
• Main Authors: Pérez-Sánchez, Alfonso, Segura, J.A., Rubio-Gonzalez, C., Baldenegro-Pérez, Leonardo A., Soto-Cajiga, J.A.
• Format: Article
• Language: English
• Subjects: Acoustic impedance; Acoustic resonance; Acoustical amplifier; Acoustics; Cavitation; Computer simulation; Design analysis; Economic analysis; Electrical impedance; Electrical properties; FEM; Finite Element Method; Frequency response; Harmonic analysis; Horn; Langevin transducer; Modal analysis; Numerical analysis; Phase; Piezoceramic stack; Resonance; Transducers; Ultrasonic transducer; Ultrasonic transducers
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2020.112035

•A complete design methodology for ultrasonic power transducers is shown.•The effects of the acoustic load on the frequency response of the transducer are analyzed.•The effects of the acoustic impedances in the interfaces of the materials are analyzed.•A comparative study of the changes introduced by the acoustic load in the frequency response is made.•The improvements in the frequency response are analyzed with the use of the parallel inductor. With the inductive compensation a very important improvement of the effective mechanical coupling factor from 0.1 to 0.55 was obtained. This paper presents the design and analysis of a Langevin Ultrasonic Transducer for Acoustic Cavitation Generation (LUTACG) operating under acoustic load. When an ultrasonic transducer is used with acoustic loads its Impedance-Frequency-Phase (IFP) characteristics change. The changes produced in its frequency response are very large and require a readjustment in the control of the resonance frequency as well as the magnitude of the voltage. In this work, a study of the effects of the load type on the impedance-phase relation is made. Experimental tests to study the changes produced in the frequency response were performed in air, water and transformer oil. The different factors that should be taken into consideration in the numerical simulation for a good mechanical-acoustic design are analyzed. Characteristics such as geometry, acoustic impedance, resonance frequency and phase which the ultrasonic transducer and sonotrode must have for proper operation under an acoustic load are analyzed. A simple and economical method is used for the electrical characterization of the transducer. An analysis of the effect of the acoustic impedance between the different interfaces and as they affect the acoustic efficiency of the transducer is made.